hot reading 25, neutral reading 120. whats wrong

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  #1  
Old 03-26-20, 10:18 AM
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hot reading 25, neutral reading 120. whats wrong

i have a 20 amp dedicated to the AC wall unit in my kitchen. i havent used it in years and forgot why not. well now i know why:

when i test white (neutral) to ground i get 120. when i test black (hot ) to neutral i get 25. black to ground barely moves the needle.

i flicked the breaker off and confirmed zero reading so i def have the right breaker. and also i'm touching the wires themselves. no outlet has been installed there in years.
 

Last edited by luckydriver; 03-26-20 at 10:38 AM.
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  #2  
Old 03-26-20, 10:44 AM
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120 neutral to ground usually means an open neutral. But you should still measure 120 hot to ground. Could this be a 240 circuit? In that case one of the hots is open.
 
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Old 03-26-20, 11:58 AM
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i guess it could be 240 but how do i know that. there was an old thru the wall unit that was directly wired up there before and i know when i went to replace it in the 105 degree day (miserable day to replace AC) that i couldnt use that for some reason. my guess is because it just had the wires there and not an outlet and i didnt wanna try to install one. so i just plugged it into an outlet 3 ft away and taped up the wires in the AC hole in the wall. . however i cannot run my full size freezer and the AC at the same time on that other circuit so i wanted to go back to using this existing ac wiring for the AC

but now that you mention it, it probably was 240 hardwired AC unit. how would this be fixed
 
  #4  
Old 03-26-20, 12:03 PM
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A 240 volt cable should be connected to double pole breaker. You could remove the panel cover and see where the black and white from the cable are connected.
 
  #5  
Old 03-26-20, 12:28 PM
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The top button on the breaker also has some other kind of weird lever on it that is not on any other breaker. But both of them in the breaker are 20 amp. Also the model number is p2020. Where the number four breaker is which is the one that I turn it on for the air conditioner there is a white wire that goes out the bottom of the box and into the wall but the black wire that comes off of the number 5 breaker is interesting. Also these are pushmatic if that matters. It leads to the top of the box where there is a cable that runs up into my ceiling. I have a 1 story house so the Box and everything is on the same level. But the point is the cable that goes out the top of the box has the black wire running to the number 5 but then the White and the ground wire in that same cable run to the top of the electrical box and are connected to a bunch of pretty impressive screws,

i do wonder if that wire that leads to the ceiling runs to the AC unit.or actually since the white wire on the breaker runs down out the bottom of the box into the wall, maybe thats it, can you tell im confused

edit should note that people hvae said my box is weird. actually i have 2 boxes. but a guy installed my hot tub and it works fine so i know i have 240 service. but people give me puzzled looks when they see the setup

i have this


https://www.pacificcoastbreaker.com/...QaAnm-EALw_wcB
 

Last edited by luckydriver; 03-26-20 at 01:33 PM.
  #6  
Old 03-26-20, 05:24 PM
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Do not connect a receptacle to that wiring without first verifying that it is 240 volts or 120 volts. You could blow up an appliance or device or electronics you plug in if the voltage is wrong.

As mentioned above, you can repurpose some* 240 volt circuits as 120 or vice versa.

For 120 volts you connect the black wire to a panel breaker terminal and connect the (must be) white wire to its own hole or terminal in the terminal strip (bus bar; with screws side by side in a row) with several other white wires.

Receptacles for 120 volts and 240 volts have different prong arrangements to help prevent incorrect connection.

* A 240 volt circuit might have black and white wires in addition to the ground wire.
 
  #7  
Old 03-26-20, 06:03 PM
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this is the breaker

https://flic.kr/p/2iJ1AQ7

i'm still confused how to tell it's 240 or 120. per what i said before: when i test white (neutral) to ground i get 120. when i test black (hot ) to neutral i get 25. black to ground barely moves the needle.

assuming i'm reading my meter correctly, doesnt neutral to ground getting 120 mean i have 120?

i found a pic on the internet of my meter and i drew in a blue line where i got my reading when the setting was at 250 on the dial. but now you do have me worried this may be 240 and i cannot afford to fry the AC. if i plugged in a cheap clock radio would that verify it? actually i did test wire up an outlet and plug it in and it wouldnt light up but maybe i wired it wrong.

https://flic.kr/p/2iJ1Gtb
 
  #8  
Old 03-26-20, 06:18 PM
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here is something interesting. all the other double breakers only have black wires. number 4 is the only one that is white. the white wire from 4, which is the AC breaker, and that wire goes out the bottom of the box to who knows where, i assume the outlet of course. the black wire coming out of breaker 5 goes up to the top where it goes out a cable run into my ceiling. coming from that cable is a white and ground wire and i circled it and you can see it runs to the bar at the top of the box. so why is there a white wire on 4 where no other white wires are? based on the spaghetti ( you cant see it in the pic) that is at the bottom of the box leading out , i'm wondering if the cable at the top was run as an after thought for the AC usage exclusively. does that make sense

https://flic.kr/p/2iJ4BCG

https://flic.kr/p/2iJ1Sn4
 
  #9  
Old 03-26-20, 08:10 PM
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White wire on a breaker is definite indication of a 240 volt circuit. Where does the black wire from the same cable as the white wire go?
Someone may have removed it to use the breaker for another circuit.
 
  #10  
Old 03-26-20, 08:29 PM
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sadly the cable where the white wire goes is in a cluster of at least 3 cables and i really dont wanna go moving anything around in the box. it sounds like the safest thing to do is just secure the wires in the wall and put a plate on it and in the case of me possibly needing the freezer plugged in in the future ill just have to run the extension cord to the next room as before. im painting my kitchen now and it was going to be a good time to put a box in and and outlet but i guess it isnt in the cards for me. i forget if there was a box in there before or not when it was just hardwired. maybe tomorrow ill be more daring and try to separate the cables.

is there any way to put that white wire somewhere else to make it 120...doubt id do it but just curious. and does that mean all the other things with black wires are 120 then. i have to assume so.most things have never even been labeled. just the things i need to do/turn off have been figured out ever.
 
  #11  
Old 03-27-20, 04:18 AM
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boy they packed the wires in there. but i'm reasonably sure that the black wire from that cable goes to another breaker on the other side of the panel. if true does that confirm 240? but if the wire goes to anothre breaker and that breaker is on, why is there no reading at the wires at the outlet?

assuming for a moment thats true that the black goes to another breaker. can i use this knowledge to make it just a 120?
 
  #12  
Old 03-27-20, 04:25 AM
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You have to find out in the panel which cable (and black wire inside) goes out to that air conditioner kitchen location.

Until then, do this:
Unhook the white wire from the panel breaker terminal and then label and tape the end.
Verify up in the kitchen outlet box that you no longer get 120 volts from the white wire.
Tape over both wires in the outlet box up in the kitchen.

To get 120 volts at that kitchen box you would connect its white wire down in the panel to the neutral bus bar (terminal strip) and connect the black wire to one of the breakers.

We will not rule out a wire from that kitchen box having been damaged due to rough handling in the box or in a junction box halfway to the panel or (extremely rare) due to a rat in the wall chewing the cable in between boxes.

... other things are 120 ...
Use your voltmeter (multimeter) instead of a clock radio to verify the voltage from hot (the slightly shorter receptacle prong slot) to neutral (the white wire or slighlty longer prong slot).

They make a two piece electronic kit (no assembly required, batteries probably not included) sometimes referred to as a toner. You clip the tone generating part onto a wire end in question and use the sensor to find the other end. It is sensitive enough that it can trace the route of wiring in the walls.
 

Last edited by AllanJ; 03-27-20 at 04:52 AM.
  #13  
Old 03-27-20, 05:36 AM
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the outlet is no longer attached but for the fun of i turned on the breaker directly across from 4. then went back to the outlet. black to white wire now gets 240. black to groudn gets 120 and white to ground gets 120.

so per your instruction it appears i just need to put the white on the top bar? id need to extend it about 12 inches to reach the top of the box. so just wire nut and tape it i assume? then unscrew the screw i have circled and put it in the white extension i installed? or actually just any screw with white under it is good i guess?

so obviuosly i should turn off that main. but how can i use my meter to verify that the juice is off? i know this sounds silly but since i have a 2nd box, im paranoid that the 1st box wont be off.

https://flic.kr/p/2iJ8Tgp

https://flic.kr/p/2iJ8UhY

edit: found some in line pushin wire connectors good from 12 to 20 gauge so that makes things easier for sure!
 

Last edited by luckydriver; 03-27-20 at 05:53 AM.
  #14  
Old 03-27-20, 06:13 AM
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You can splice on an extra length of wire of the same size and color using a wire nut to reach a terminal strip or breaker as needed. Just twisting the connection is not good enough.

Avoid using push in wire connectors for switches, receptacles, etc. They tend to have more loose connection problems years later compared with screw connections.

Each neutral (white) wire must have its own terminal or hole in the strip (bus bar). Two ground wires may share the same hole if they are the same size and are not touching each other when fastened in place.

Pigtail: A length or segment of wire (not cable) completely within a box or enclosure.
 
  #15  
Old 03-27-20, 06:53 AM
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as u can see in the pic there are multiple white wires in a terminal. i dont see any spares either. seesm like this is how it was done in the 50s. i wouldnt know where to put it. u see anything?
 
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Old 03-27-20, 06:59 AM
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How many of the terminals or holes in the bus bar have ground wires in them?

You can pigtail two or three ground wires to one hole so as to free up more holes for neutrals.

Do not loosen a neutral untill after the breaker for that branch circuit or cable has been switched off. (If a neutral got unhooked and something on that branch circuit was energized and switched on, you will measure 120 volts between the loose end of that neutral and the place it used to be attached to!

For testing you might temporarily share a terrminal between two neutrals. But eventually and soon you may need to buy another terminal strip, attach it to the back of the panel box, and move some of the ground wires over to it.
 
  #17  
Old 03-27-20, 07:34 AM
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ah ok i didnt realize the bare ground wires in the back of the white wires are all hooked up there. this is all new to me

do you see in the one pic above that there are 2 terminals each wiht a bunch of white wires jammed in there? next to those jammed up terminals are screws with nothing in them at all. but they are more flush mount. why would someone jam wires in that terminal vs using the open screws.

but the main question is, can i just put my new white wire under one of those unused screws next to the jammed up terminals. or must just the bare grounds be in the lower screws and the white wires must be in the raised terminals

-----------
so sounds like i should switch off the main...switch off the breaker where my white wire is...disconnect white wire..wirenut new section of white wire..then put that other end of white wire into the terminal in the bar above..then that new breaker across from this one becomes the AC 120 line.

sound correct?
 
  #18  
Old 03-27-20, 08:17 AM
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You have verified that the breaker opposite #4 energizes the black wire up in the kitchen box. Flip it off and measure up in the kitchen, then flip it on and measure it up in the kitchen to re-reconfirm. Then leave it off.

Yes, flip off the breaker with the white wire. Unhook the white wire in the panel.

Verify that the white wire is now dead up int eh kitchen.

For now hook up that white wire to one of the unused screws in back of the neutral bus bar. (Later you will need to sort things out up there).

Now you should have a good 120 volt circuit into that kitchen box. Measure again to re-reconfirm.

Double check or replace the breaker opposite #4 so is no more than 20 amps.
 

Last edited by AllanJ; 03-27-20 at 09:52 AM.
  #19  
Old 03-30-20, 10:32 AM
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got around to doing this finally and i did something wrong. i did everything i was supposed to and had the outlet wired but didnt yet push it back in the box. with the juice on i touched the metal part of the outlet and it was energized. the part where the screw is attached. zoinks. not supposed to do that of course

black to ground is 120..black to white is 120 . black to metal part of outlet is 120

i did put the white wire in the electrical box up to the neutral bar and kept breaker 4 off. now 5 is that outlet. note i'm using a plastic box and also that my plug in tester says this is wired correctly
 
  #20  
Old 03-30-20, 10:45 AM
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When it is all done the ground wire should be attached to the (usually) green screw on the metal part of the receptacle unit up in the kitchen.

Then
... black to ground is 120..black to white is 120 . black to metal part of outlet is 120 ...
should be true.
 
  #21  
Old 03-30-20, 12:18 PM
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green has the ground but is it normal to touch the metal part of the outlet (i was going to screw in the outlet to the box) and the outlet shock you? gotta admit i dont play with outlets much

i just had figured it was live and no biggie to just screw it in the box, and i got a surprise. and i guess since the box is plastic and the cover is plastic the juice cant to anywhere but i still think its weird.
 
  #22  
Old 03-30-20, 04:04 PM
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looks like the outlet was bad. i just had it laying around. it was a single outlet. i found a new in box dual outlet and hooked it up and didnt fry myself! not just gotta make it permanent instead of outside the box

thanks for all the help
 
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